Automatic voltage regulator



March 4, 19-41. DEBREY v 2,234,110

AUTOMATIC VOLTAGE REGULATOR Filed Jar a. 22, 1937 2 sheds-sheet 1 Mick a Debra March 4, 1941. DEBREY 2,234,110

AUTOMATIC VOLTAGE REGULATOR Filed Jan. 22, 1957 2 Sheets-Sheet 2 Patented Mar. 4, 1 941 UNITED STATES PATENT OFFICE 4 Claims.

This invention relates to an improved automatic voltage regulator and is more particularly intended for use with generators of various types.

One object of the invention is to provide a voltage regulator which will be operable for automatically short circuiting a regulator resistance in the field circuit of a generator exciter whereby intermittent increased excitation of the generator by said exciter will be provided so that sudden loads on the generator will not cause impairment of operation of said generator.

Another object of the invention is to provide an automatic voltage regulator which will be simple in construction and capable of easy installation, and which will not require the use of a field relay or other supplementary attachments.

A further object of the invention is to provide a device of this nature which will be of the vibrating contact type and which will embody a core whichis operatively responsive to the frequency of alternating current developed by the generator for vibrating the contacts employed.

A further object of the invention is to provide an automatic voltage regulator wherein means are embodied for permitting adjustment of the contacts so that the operation of the device may be effectively regulated.

And the invention seeks, as a still further object, to provide an automatic voltage regulator employing an inductively coupled secondary coil which will be energizable, when thegenerator is under load, for permitting a time lag in the open ing and closing of the contacts.

Other and incidental objects of the invention, not specifically mentioned in the foregoing, will render themselves apparent during the course of the following description.

In the accompanying drawings:

Figure l is a diagrammatic view of my improved voltage regulator and showing certain of the working parts thereof in elevation.

Figure 2 is a fragmentary end view of the dethe requirements of individual installations, and is adapted to be secured to a panel or wall 2, preferably at right angles thereto, by bolts formed integral on blocks 3 which are mounted on the base in parallel spaced relation to each other, and which are preferably formed of light weight metal.

Carried on the base I and disposed in parallel spaced relation to the innermost block 3, is a yoke l which includes a bight portion 5 having an extended portion 6 terminating in a bolt which, like the bolts formed on the blocks 3, extendsinto the panel 2. The yoke also includes upstanding arms I and 0 which are spaced along the length of the bight portion 5 and are adapted to receive, at their corresponding upper end portions, pivot bolts 9 and In which are disposed in horizontal alinement in opposed relationship.

The yoke is adapted to have pivotally mounted therein a contact supporting member indicated in general by the numeral II and which includes a relatively long lever portion 12 and a relatively short' arm 13. The lever portion I2 is adapted to extend above the base I normally in parallel spaced relation thereto and terminates near the end of the base. The lever portion is provided with an eye bolt H which receives the lower end of a coil spring I5. The upper end of the coil spring I5 is supported by an adjusting bolt 16. The adjusting bolt 16 is mounted in a relatively long overhanging block I! which is mounted on the panel 2 by means of a screw l8 which extends through the paneland into the inner end portion of said overhanging block clockwise or counterclockwise direction for raising or lowering the bolt with respect to the lever portion l2 and resiliently tightening or loosening the tension of the spring 15.. The'bolts 9 and 10 are, of course, adjustable for mounting the contact supporting member ll so that it will be firmly mounted and yet free to rock between the arms I and 8 of the yoke. I The contact arm 13 is adapted to have adjustably mounted thereon, at its upper end, a contact screw [9 which terminates in a contact 20. The contact screw is threaded through the upper end of the arm 13 and is normally held in a set position by a lock nut 2!. An adjusting screw 22 is threaded through the arm it below the contact screw 19 and has a head 23 thereon. The screw 22 is normally held in a fixed position by means of: a lock nut 24.

Mounted on the base I and disposed between The adjusting bolt may be rotated in a the yoke 4 and the blocks 3 is an upstanding arm or standard 25 which has a base portion 28 and a relatively long arm 21 which is reduced in thickness throughout the major portion of its length. The arm 21 is adapted to be disposed in longitudinal aiinement with the relatively short arm ll oi the contact supporting member ii and is also adapted to be secured to the base portion thereof by means of a locking screw 28. Carried on the standard and secured to the relatively long arm 21 is a relatively long spring contact member I! which is adapted to support at its upper end portion a vcontact pin I0. The contact pin ll extends at opposite sides of the upper end portion of the relatively long spring contact member and, at one side of said member, extends through an opening ll in the arm 21 to terminate in a head 82, which head limits swinging movement of the spring contact member away from the arm 21. At the opposite side of the spring contact member, the pin 8| extends at right angles to said member and terminates in a contact ll which is disposed in alinement with the contact II and is adapted to cooperate therewith. In order to permit adjustment of the spring contact member 2!, 1 provide a spring adjusting screw It. The spring adiusting screw is adapted to be screwed through the lower end portion of the relatively long arm and to abut, at its free end, the under surface of the spring contact member 2!.

Associated with the contact supporting member ii and connected with the lever portion II thereof near the yoke l is a plunger rod 38. As best seen in Figure l of the drawings, the plunger rod extends upwardly through the base, through the base portion of the standard 28, and is pivotally connected with said lever portion II. The lowerendoftheplungerrodllissecuredtoa solenoid plunger 80 which is adapted to be disposedwithinaprimarymagnetcoilllanda secondary magnetic coil ll. The lower end portion of the solenoid plunger is provided with aitself at its upper end to The spring is connected it by means of a relatively small spring is adiustably mounted on aaidarmuby meansoi'aboltll. 'lhe'arm be in longitudinal alinement short am It of the contact In 1 of the drawings, I have shown diagrammatically the circuit arrangement of my improved automatic voltage regulator and by again referring to this figure, it may be seen that the numeral 49 indicates, in general, a generator exciter including a field coil I and an armature ii. The generator exciter also includes in the circuit a iield exciter rheostat 52. The exciter 48 is electrically connected with a generator 53 which, in the present instance, is an alternator for generating alternating current 01' preferably low frequency. The alternator includes a field winding 54 and an armature I, and said alternator also includes a field rheostat 58. The alternator and exciter may be built in one casing, or separately, as preferred. The alternater is connected with the primary mag net I? by means of conductors I1 and 58 and the contacts II and 33 are connected to opposite terminals of the exciter field rheostat by means of conductors 59 and 60. A condenser OI is preferably shunted across the contacts and 33 so as to prevent pitting such as would be caused by repeated sparking of the contacts II and 33..

The secondary magnet coil ll has a variable resistance or rheostat 82 shunted thereacross and said rheostat includes a resistance 03 and a variable arm 64. The rheostat has one, end thereof connected to the arm i4 and to the end of the magnetic coil to which said arm is con nected, by means of a conductor ll. It will be seen that the portion of the rheostat '2 which is not in use will be short circuited and will be of no inductive eifect.

In use, after my improved voltage regulator has been installed, the operation will be as follows: The alternator I3 will supply current through the conductors 61 and II to the primary magnet coil 51 for energizing said coll. As the coil is energized, the solenoid plunger 3! is raised within the primary and secondary magnet coils I1 and ll for shifting the plunger rod upwardly and rocking the lever II of the contact supporting member ll upwardly so that the relatively short arm II of'the contact member will be rocked away from the relatively long arm 21 of the standard II. The contacts I. and 33 will be separated and the exciter field rheostat I! of, the exciter II will be retained in the circuit so that the Output of the exciter ll will be reduced. with consequent lowering of the voltage of the alternator II. As the voltage of the alternator II is lowered, the energization of the primary and secondary magnet coils 31 and a will be reduced so that the solenoid phmger a will bepermitted to drop. The plunger rod 3' will, of course, drop and will rock downwardly the lever II of the contact supporting member ll so that the relatively short arm II. will be swung toward the standard ii for engaging the contacts II and 18. When the contacts 2| and N are engaged, the exciter rheostat II will be short circuited so that the full output of the exciter will be impressed upon the alternator with the result that the alternator voltage will be increased for again raising the solenoid plunger and breaking the circuit between the contacts II and a and again introducing the field rheostat into the circuit. It should be understood that the making and breaking of the contacts II and II will be done ata high rate ofspeedsothatitmaybesaidthat the contact supporting member provides a vibrating connection between said contacts 2| and 38. The contact plunger II will be caused to move upwardly and downwardly at the frequency or the cur? rent generated by the alternator so that the contacts will be caused to make vibrating connection at this frequency. v

The secondary magnet coil 38, which is only inductively coupled with the primary magnet coil 31, permits a slight time lag between the contacts 20 and 33. The contacts 20 and 33 will lag, or rest, at low frequency in both the open and closed positions. By low frequencies is meant frequencies under one hundred and thirty cycles while by high frequencies is meant frequencies above one hundred and thirty cycles. When the device is being used for high frequency work, the secondary magnet coil will not. be employed as the primary magnet coil 31 will function with complete success. If desired, the secondary coil may be eliminated at all frequencies but it has been found that said secondary magnet coil increases the efliciency of the device at low frequencies. The response of the secondary magnet coil II is, of course, controlled by the rheostat $2.

In view of the fact that the contact 33 is mounted on the spring contact member 2!, a proper amount of lag during the opening and closing of the contacts will take place so that the exciter will operate at full output for a long enough space to permiti the alternator to again pick up suflicient current to energize the primary coil for again breaking the circuit and preventing over-excitation of the generator.

Ordinarily, the relatively short arm I3 is in such a position relative to the spring supporting post ll that the head 21 of the adjusting screw 22 will be out of engagement with the stop face I of the spring 45. If, however, too great excitation of the alternator should take place, the solenoid plunger 36 will shift upwardly far enough for engaging the head 23 with the spring 45. Said spring will, therefore, prevent too great shifting movement of the contact supporting member II. The spring i which is connected to the lever l2 and to the adjusting bolf- Ii, will cooperate with the solenoid plunger for retaining the contacts 20 and 33 in proper operative position. The spring adjusting screw 34 may, of course, be adjusted for regulating the amount of lag to take place between the contacts 2| and 33. It is believed that the construction and operation of my improved automatic voltage regulator will be clearly understood from the foregoing so that further description is deemed unnecessary. It should also be understood that minor changes in the construction may be made without departing from the scope of the invention.

Having thus described the invention, what I claim is:

1. In an automatic voltage regulator, a base, a yoke carried by the base, a contact supporting member carried by the yoke and having a relatively shortarm and a contact, a standard carried by the base and having a relatively long arm, a relatively long spring contact member carried by the standard, a contact on said con- 1 tact member and being adapted to cooperate with said first mentioned contact, said contact supporting member including a lever, a magnet coil, a solenoid plunger carried by the magnet coil and having a plunger rod connecting said solenoid plunger and said lever, a spring supporting post carried by the base, and a spring carried by the post and limiting rocking movement of the contact supporting member.

2. In a voltage regulator, supporting means, a voltage coil carried by the supporting means, a core movably mounted within the coil, a yoke on the supporting means, a contact supporting member movably carried by the yoke, a contact on said contact supporting member, a standard on the supporting means, a spring contact member on the standard, a contact carried by the spring contact member and engageable with the first mentioned contact; and means carried by -the spring contact member and en a eable throughthe standard for'limiting movement of the last mentioned contact away from the standard, said voltage coil being energizable from the alternating current source for floating the core within the coil inan oscillatory manner and vibrating the contacts at the frequency of the alternating current source, said spring contact member permitting a lagging vibratory connection at the alternating current frequency between the contacts upon dropping of the voltage in the voltage coil so that the regulating means will be operative for increasing the'voltage immediately to compensate for I an increased load.

3. A voltage regulator .Jincluding supporting means, a contact movably mounted on the.supporting means, a standard on the supporting means,.a spring'contact member on the standard and having a contact, means adjustably connecting the last mentioned contactwith'thestandard, said contacts engageable in a vibratory manner, means-,for' adjusting the tension of thespring contact "member whereby the response of the contacts may be controlled, and voltage responsive means on the supporting means and being'connected with the first men-- tioned contact.

4. In a voltage regulator, a base, a yokeon the base, a contactsupporting member movably mounted in the-yoke andihaving arms, 'a contact carried by one ofthe arms, a voltage coil carried by the base. a solenoid plunger movable in the voltage coil and being connected with the other of the arms of the contact supporting member, a standard on the base, a spring con tact member on the standard and having a contact, means adjustably connecting a portionof the spring contact member and the second men tioned contact with the standard, said contacts being engageable in a, vibratory manner, and means on the standard and engageable with, the spring contact member for adjusting the'tension of said springcontact member whereby the speed of vibratoryengagement of the contacts may be controlledsaidcontacts being engageable at the speedof the-frequency of an alternating current source energizing the voltage coil. 1

' wJ'IICI-IAEI-IDEBREY. 

